This equipment request is for a Bruker Skyscan 1176 in vivo high-resolution three-dimensional (3D) microcomputed tomography (CT) system. High-resolution in vivo CT is the gold-standard technology for assessment of bone microarchitecture in small laboratory animals. In addition, this state-of-the-art technology can simultaneously assess small animal (mouse/rat) whole-body body composition and 3D soft tissue characteristics (e.g., muscle cross-sectional area, adipose tissue volume, lung volume, etc). The integrated physiologic monitoring system (including ECG, breathing detection, and temperature stabilization) allows for gated/time-resolved 4D microtomography of whole-organ (e.g., heart, lung, etc) and vascular characteristics in mouse/rat (following perfusion with a contrast agent). Accompanying hardware/software provides the ability to reconstruct 2D datasets into 3D models for data analysis, quantification, and visualization. Acquisition of an in vivo high-resolution 3D CT system will greatly enhance the quality of research at North Florida/South Georgia Veterans Health System (NF/SG VHS) and our academic affiliate, University of Florida (UF), and will improve likelihood of future VA and non-VA grants which is increasingly dependent upon use of state-of-the-art technology. Importantly, no similar equipment currently exists at NF/SG VHS or UF. We have identified nine (VA and/or UF) investigators who have current VA/NIH funding and have expressed serious interest in utilizing this equipment to improve their individual and collaborative research programs. In particular, the primary uses of this in vivo 3D/4D CT system will be to assess the longitudinal (chronic) effects of neurotrauma (i.e., spinal cord injur or traumatic brain injury), bone injury, aging, and/or obesity on bone microarchitecture, muscle cross-sectional area, vascular characteristics, and body composition in small animal models. In this manner, we can acquire simultaneous data on multiple organ systems that are affected by the aforementioned conditions and can design and test appropriate pharmacologic/physiologic interventions to address the identified deficits. Ultimately, the long-term goal of this proposal i to ensure the acquisition of more robust basic/preclinical data regarding a variety of deleterious conditions that are highly prevalent in the Veteran population and to more aptly progress these findings to clinical trials, which will benefit the health of Veterans who experience the aforementioned conditions.